To do that open up your Putty and login to the server as root and write the following code in the terminal.
Remove nginx cache CENTOS 7
rm -rf /etc/nginx-cache/*
The above code will work only if you set the cache nginx folder to be nginx-cache. If you have other folder set as cache for nginx you will have to find it first.
Type in terminal:
cd /etc/nginx - this will open nginx folder then: nano nginx.conf
In nginx.conf you should find all settings for nginx. Let me know if you need any help.